Interrelations of markers of pubertal development (endocrine status, pubertal stage, and physical growth) and adolescent adjustment are investigated cross-sectionally and longitudinally. Participants are 9- to 14-year-old boys and girls and their parents. The adolescents and their parents are seen three times, six months apart. The markers of pubertal development include serum hormone levels (gonadotropins, sex steroids, and adrenal androgens), pubertal stage (Tanner criteria), and height and weight. Psychological assessments of the adolescent include measures of behavior problems, self-image regarding various domains of functioning, and self- and parent-perceptions of the adolescent's physical, cognitive, social, and overall competence. Cross-sectional hormone data for Time 2 and 3 were analyzed for the comparison with interrelations based on Time 1 data. In general, findings were replicated. Biological changes across Times 1-3 were examined to determine the rate and trajectory of biological change during the one-year period of the study. These analyses inform our tests for linear and nonlinear effects of biological processes on psychological functioning. Ongoing analyses of predictive relations between Time 1 biological measures and Time 3 psychological measures confirm some important findings from cross-sectional analyses. For example, higher levels of androstenedione and lower dehydroepiandrosterone sulphate levels continue to be associated with behavior problems. Timing of maturation as well as rate of biological change (in physical maturity for boys and hormone levels for girls) also predicted psychological functioning at Time 3. Analyses are planned to generate hormone profiles, so that individual hormone profiles may be examined in relation to competencies and dysfunctions in psychological domains.